Extremely awful. So much wasted space. Why the **** is everything squished to the left side? I have a 1920x1200 resolution, and I may as well be on 800x600 for this crap. Good thing there are a few userstyles and userscripts available to help make this change not as horrible. Unfortunately, all of my old scripts are broken. That is kind of a deal breaker for me.

just delete your youtube cookies if you want to go back to the old layout

it's not permanent yet

edit: or maybe it is permanent now i had just got it for the first time today and was able to revert it back by deleting the youtube cookies, but now it's back to the new layout again and i can't get it back